Slight mishap, now looking for bargain cranks

I've been pretty lucky over the years when it comes to breaking stuff. A few punctures and I think I once pulled the hose out of my rear brake calliper. A pretty good record given my utter ineptitude and tendency to fall off spectacularly on the most innocuous bits of trail. I even had a 2009 Meta 5 that didn't crack.

However, today I was 15 minutes into my first loop round Cathkin Braes when I put a wee bit of power down to get up a short climb and promptly sheared all four chainring tabs off of my cranks. OK, so they're 4 or so years old and I had to take a few liberties to get them to run 10 speed, but I'm 10.5 stone and pretty feeble so it was a trifle unexpected.

Anyway, to belatedly get to the point (if anyone has bothered to read this far), has anyone spotted anything that's more bargainly than Merlin's 75 quid for an X9? 170mm and 10speed would be nice, but frankly I'll take what I can get up to the point where they offend my vanity (so that rules Deore out).

Actually that is the only difference between my XT and Deore. The logo wore off the Deore and didn't from the XT. I presume if I weighed them there would be a difference but functionally they are identical. Recent offers on XT at Merlin have had me thinking about swapping the Deore but what would be the point?